Grinding attachment



\ J. H. GREEN GRINDING ATTACHMENT Jam 13, 1970 3 SheetsSheet 1 Filed Jan. 5, '1968 Fig./

0 w mm 2 Q James H. Green INVEN TOR.

O BY Mao/5M Jan. 13, 1970 J. H. GREEN 3,488,894

GRINDING ATTACHMENT Filed Jan. 5. 1968 3 Sheets-Sheet 2 mm mm m m M m M W W .7 Wm r W 9 MM m v E s M Y .e wn g QM a g PK r X. Y Ill ni B Wm ,8 JV l L mm om m m T t mw mm vw mm ww J Vv Q QM {11. a.) 8 3i m mm mm fi gm w. aw av a 3 G 8 w E Q United States Patent 3,488,894 GRINDING ATTACHMENT James H. Green, P.O. Box 232, Pensacola, Fla. 32502 Filed Jan. 3, 1968, Ser. No. 695,514 Int. Cl. B24b 19/00, 47/02 US. Cl. 51-225 9 Claims ABSTRACT OF THE DISCLOSURE An attachment mounted on a grinding machine for sharpening spiral fluted tools. The tool is clamped to the end of a driven shaft mounted by the attachment for axial movement by an actuating lever which simultaneously imparts angular movement to the shaft through gearing coupled to the shaft. The drive ratio of the angular-to-axial movement may be adjustedto accommodate the spiral of the fluting while the driven shaft may be angularly indexed relative to the gearing before the tool is displaced through an operative stroke.

This invention relates to the grinding of spiral fluted tools such as end mill cutters and more particuarly to a tool holding attachment through which a standard grinding machine may be converted into a grinder for cutters having spiral blades or fluting.

In order to grind spiral surfaces onv workpieces such as spiral fluted tools or spiral bladed cutters, it is necessary to feed the workpiece toward the grinding wheel and at the same time angularly displace the workpiece about the axis along which the workpiece is fed. Any work holding attachment must accordingly accommodate such simultaneous linear and angularmovement of the workpiece as well as to provide facilities for varying the drive ratio between the linear and angular movement in accordance with the degree of the spiral surface being ground. Also, facilities must be provided in order to angularly index the workpiece.

In accordance with the present invention, the work holding and feeding attachment when adjustably secured to the frame of the grinding machine, produces axial movement of a driven shaft to which the workpiece or tool is clamped by a collet chuck when an actuating lever is displaced through a predetermined stroke. An adjustable fulcrum is associated with the actuating lever in order to change the drive ratio of linear-to-angular movement produced by gearing mounted on the actuating lever through which angular movement is imparted to the driven shaft while it is being axially displaced. The gearing is coupled to the driven shaft through an axially shiftable coupling element which may be displaced to an adjusting position for angularly indexing the driven shaftat the beginning of an operating stroke of the shaft and the actuating lever. In this fashion, a plurality of parallel spiral surfaces may be ground on the workpiece or cutting tool clamped to the driven shaft.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view showing the attachment of the present invention.

FIGURE 2 is a longitudinal sectional view through the attachment taken substantially through a plane indicated by section line 22 in FIGURE 1,

FIGURE 3 is a rear elevational view of the attachment with parts broken away and shown in section.

3,488,894 Patented Jan. 13, 1970 FIGURE 4' is a top plan view of the attachment shown in FIGURES 1-3.

FIGURE 5 is a transverse view taken substantially through a plane indicated by section line 5-5 in FIG- URE 4.

FIGURE 6 is -a trans-verse view taken substantially through a plane indicated by section line 66 in FIG- URE 2.

FIGURE 7 is a top section view taken substantially through a plane indicated by section line 7-7 in FIG- URE 2.

FIGURE 8 is a partial side sectional view through the attachment shown in its adjusting position for angularly indexing the driven shaft.

Referring now to the drawings in detail, it will be observed from FIGURE 1 that the attachment generally referred to by reference numeral 10 is adapted to be secured by means of base plate 12 to the angle plate associated with a conventional shop tool grinder in order to align the workpiece 14 with the grinding wheel (not shown). The grinding wheel is adapted to grind the spiral surfaces or flutings 16 formed in the workpiece such as the spiral end mill cutter shown. The cutter tool is adapted to be clamped by means of a conventional collet chuck 18 to the grinding end of a driven shaft 20 slidably mounted by the base plate 12 in order to feed the cutter tool toward the grinding wheel. The base plate 12 is secured by means of the fasteners 22 to a bracket 24 to which a slide bracket 26 and an adjustment bracket 28 are secured to form a frame assembly. Linear axial movement is imparted to the driven shaft 20 and the workpiece or tool 14 by means of an actuating lever 30 pivotally and slidably mounted by the frame assembly. Gearing 32 is rotatably mounted by the actuating lever so as to impart angular movement to the driven shaft 20 about its longitudinal axis at a predetermined drive ratio to its axial movement in response to oscillation of the actuating lever 30. This drive ratio is established by the adjusted position of a fulcrum device 34 mounted by the adjusting bracket 28. Positional adjustment of the fulcrum device is effected through a spiral adjusting knob 36 in a manner tobe hereafter explained in detail while the driven shaft 20 may be angularly indexed by means of the adjusting knob 38 as will also be explained later.

The driven shaft 20 is slidably mounted on the base plate 12 by means of the spaced clamps 40 and 42. The shaft is hollow and internally shouldered at the work end so as to receive the work holding collet chuck 18 as more clearly seen in FIGURE 2. The opposite end of the driven shaft includes an internally enlarged coupling portion 44 provided with a plurality of longitudinal grooves 46, twelve of such grooves being provided in the illustrated embodiment. The grooved coupling portion is spaced from the end of the driven shaft and opens into a further internally enlarged bearing portion 48 within which a socket member 50 is rotatably mounted. The socket member as shown in FIGURE 6 is also provided with twelve coupling grooves 52 that are aligned with the grooves formed in the coupling portion 44 of the driven shaft. A six-sided coupling element 54 engages alternate grooves in the coupling portion 44 and the socket member 50 in order to rotationally couple the socket member to the driven shaft for torque transmitting purposes. The socket member 50 projects axially from the end of the driven shaft through an opening in a flange type end clamp 56. The end clamp is secured to the end portion of the driven shaft abutting the washer 58 as shown in FIGURE 2. A stop clamp 60 is secured to the driven shaft in an axially adjusted position between the end clamp 56 and the base clamp 42 in order to predetermine the reciprocatory stroke of the-driven shaft when displaced in an axial direction by means of the actuator lever 30.

Angular movement is imparted to the driven shaft 20 through the driven bevel gear 62 secured to the socket member 50 and associated with the gearing 32. The driven bevel gear is rotated about the rotational, longitudinal axis of the driven shaft by means of the drive bevel gear 64 with which it is enmeshed, the drive bevel gear being rotatably mounted about a vertical axis disposed in perpendicular intersecting relation to the rotational axis of the driven gear 62 and the driven shaft to which it is coupled by means of the coupling element 54. The vertical axis about which the drive bevel gear 64 is rotated, also constitutes the pivotal axis about which the actuating lever 30 in angularly displaceable relative to the frame assembly. The gears 62 and 64 are supported for rotation about their respective axes by means of a gear holder 66 which includes a tubular horizontal portion 68 and a vertical shaft portion 70 through which the pivotal axis extends. A tubular support member 72 extends through the horizontal portion 68 of the gear holder assembly and supports thereon the socket member 50 for rotation about the rotational axis of the driven shaft. Thrust bearing Washers 74 are disposed between the end of the socket member and the horizontal portion 68 of the gear holder. The tubular support member 72 is locked in axially assembled relation to the horizontal portion 68 by means of the locknuts 76 threadedly mounted on the tubular support member 72 in abutment with the portion 68 of the gear holder opposite the thrust washers 74. The drive gear 64 on the other hand is held assembled on the shaft portion 70 of the gear holder in abutment with the shoulder portion 78 by means of the setscrew 80. The drive gear is also formed with a bearing portion 82 which pivotally mounts the actuating lever 30 about the pivotal axis extending through shaft portion 70. Threadedly mounted at the lower end of the shaft portion 70, is a spherical bushing element 84 received in a guide slot 86 formed in the bracket assembly 26 which is mounted in an adjusted position on the bracket 24 by means of the fasteners 88 as more clearly seen in FIGURE 3 in order to guide movement of the gear holder in a direction parallel to the rotational axis of the driven shaft 20 along which it is axially displaced by the actuating lever.

The actuating lever includes an intermediate portion 90 through which the bearing portion 82 of the drive gear extends. Extending laterally from the pivotal axis of the actuating lever is a handle portion 92. On the opposite side of the intermediate portion 90 of the actuating lever, a slotted portion 94 extends overlying the laterally extending bracket 28 which is secured to the bracket 24 by means of the fasteners 96. The fulcrum device 34 which consists of the head 97 mounted on a slide block 98 is slidably received in the slot 99 of the lever portion 94. An adjustment screw member 100 threadedly extends through the slide block 98 and is rotatably mounted in the bracket 28 by means of the flanged bearing bushing 102 to which the adjustment shaft is fixedly secured. The spiral adjustment knob 36 is secured to the bushing 102 by means of the setscrew 104. It will be apparent therefore, that upon rotation of the adjustment shaft 100 by the knob 36, the fulcrum block 98 will be axially displaced along the adjustment screw in order to change the position of the fulcrum device which establishes a point about which the actuating lever is pivoted and with respect to which the actuating lever is slidable. For any adjusted position of the fulcrum device 34, a fixed spacing is established between the fulcrum point and the rotational axis along which the driven shaft is axially displaced by angular movement of the actuating lever through its handle portion 92. In view of the meshing relationship between the drive gear 64 rotatably mounted on the actuating lever about the pivotal axis intersecting the rotational axis of the driven shaft 20 and the driven gear 62, angular movement will be imparted to the driven shaftat the-same time that it is axially displaced as long as the driven gear is coupled to the driven shaft by the coupling element 54. Further, for any adjusted position of the fulcrum device 34, there will be a fixed drive ratio between the axial movement of the driven shaft and its angular movement. Thus, by changing the position of the fulcrum device 34 by means of the spiral adjustment knob 36, this drive ratio may be changed in order to accommodate different spiral angles.

The coupling element 54 is secured to a shift rod 106. The shift rod extends through the tubular support member 72 of the gear holder assembly and is connected to the indexing knob 38. When the shift rod 106 is in a coupling positionas shown in FIGURE 2, the coupling element 54 abutstheend of the tubular support member 72 and is disposed between the coupling portion 44 and the socket member 50 engaging the aligned grooves therein as shown in FIGURES 2 and 6. On the other hand, when the shift rod 106 is inwardly displaced to an adjusting position as shown in FIGURE 8, the coupling element 54 will be coupled only to the driven shaft 20. The index knob 38 may then be rotated in order to angularly displace the driven-shaft relative to the driven gear 62 Without any axial movement of the driven shaft so that the workpiece or tool being ground may be angularly indexed in order to. align the grinding wheel with another flute 16. Such indexingof the workpiece is effected at the end of the return stroke of the actuating handle when the workpiece is withdrawn from the grinding wheel.

From the foregoing description, the'construction and functions of the attachment will be apparent. After the attachment is adjusted for a particular spiral angle through the spiral adjustment knob 36, the actuating lever 30 is rearwardly, retracted to the beginning of its feed stroke. The indexing knob 38 may then be displaced axially inwardly and rotated in order to properly index the workpiece relative to the grinding wheel. After the workpiece is indexed, the knob 38 is pulled outwardly to the coupling position so that the coupling element 54 may interconnect the driven shaft with the gearing 32. The actuating lever may then be forwardly displaced by means of the handle portion 92 in a forward or feeding stroke direction. The length of the stroke will have been adjusted by positioning the stop 60 so as to correspond to the axial length of the workpiece 14. The grinding wheel will accordingly grind the spiral surface of the fluting as the driven shaft is being fed in an axial direction since the driven shaft is then also being angularly displaced in accordance with the spiral angle. The workpiece may then be displaced in a return stroke direction by means of the actuating lever and after it is withdrawn from the grinding wheel, it may be indexed once again through the indexing knob 38 as aforementioned.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A grinding attachment for controllably moving a workpiece comprising a driven member having a work holding device, frame means slidably mounting the driven member for linear movement through a predetermined stroke, fulcrum means mounted by the frame means in fixed spaced relation to the driven member, actuating means slidably engageable with said fulcrum means and pivotally connected to said driven member for displacement thereof through said stroke, and gear means rotatably mounted by the actuating means in driving engagement with the driven member for angular movement thereof about a rotational axis at a predetermined drive ratio to said linear movement.

2. The combination of claim 1 including means for adjusting the spacing of the fulcrum means from the driven member to change said predetermined drive ratio.

3. The combination of claim 2 including indexing means for changing the angular position of the driven member relative to the gear means to index the work holding device.

4. The combination of claim 3 wherein said gear means comprises a gear holder pivotally mounted by the actuating means about a pivotal axis intersecting the rotational axis of the driven member, a drive gear rotatably mounted by the holder about said pivotal axis, and a driven gear rotatably mounted by the holder about said rotational axis in meshing engagement with the drive gear.

5. The combination of claim 4 wherein said indexing means comprises a coupling element drivingly connecting the driven gear to the driven member, shifting means movably mounted by the gear holder for displacing the coupling element from a coupling position to an adjusting position engaging only the driven member, and adjusting means connected to the shifting means for angularly displacing the driven member relative to the driven gear only in the adjusting position of the coupling element.

6. The combination of claim 1 including indexing means for changing the angular position of the driven member relative to the gear means to index the work holding device.

7. The combination of claim 6 wherein said indexing means comprises a coupling element drivingly connecting the driven means to the driven member, shifting means movably mounted by the gear means for displacing the coupling element from a coupling position to an adjusting position engaging only the driven member, and adjusting means connected to the shifting means for angularly displacing the driven member relative to the driven means only in the adjusting position of the coupling element.

8. The combination of claim 1 wherein said gear means comprises a gear holder pivotally mounted by the actuating means about a pivotal axis intersecting the rotational axis of the driven member, a drive gear rotatably mounted by the holder about said pivotal axis, and a driven gear rotatably mounted by the holder about said rotational axis in meshing engagement with the drive gear.

9. The combination of claim 8 including means for adjusting the spacing of the fulcrum means from the driven member to change said predetermined drive ratio.

References Cited UNITED STATES PATENTS HAROLD D. WHITEHEAD, Primary Examiner US. Cl. X.R. 51232 

